A Study On Micro-nano Particles Synergistically Toughened Carbon Fiber Composites

The anisotropy of the unidirectional carbon fiber composites and the crosslinked network structure of the resin matrix can easily lead to delamination damage or interlayer fracture.Therefore,the toughening research of composite materials is of great significance.At present,the toughening methods mainly include resin matrix modification,Z-direction toughening,and interlayer toughening.Among them,interlayer toughening is an important direction for the development of advanced composite materials.Therefore,this paper compares the effects of self-assembling micro/nanoparticles of different processes on the interlaminar toughened carbon fiber composites.At the same time,the structural changes of the self-assembled micro/nanoparticles at high and low temperature melting points are studied and a mechanism model of interlayer toughening is established.1.The toughened epoxy matrix was prepared by self-assembled micro-nanoparticles(PA-MWNTs)and micro-nanoparticles(PA+MWNTs),and the mechanical and rheological properties were studied.Micro-nanoparticles were used to prepare toughened films.The mechanical properties and micro-morphology of inter-layered synergistic toughened carbon fiber composites were compared.Toughening mechanism was also discussed.Compared with the direct blending method(PA+MWNTs),the self-assembled micro-nanoparticles(PA-MWNTs)have a more pronounced toughening effect on the resin matrix,the agglomeration of the carbon nanotubes decreases,and the interlamellar coordination of the composite material.The toughening effect is even more pronounced,and is also higher than that of composites made of PA micron particles or nano-particles reinforced with MWNTs.A micro-nanoparticle self-assembly model and a synergistic toughening composite material model have been established.2.Two different melting point thermoplastic polyamide(PA)microparticles and carbon nanotubes were used to prepare self-assembled micro-nanoparticles PA-MWNTs,and different micro/nanoparticle interfacial toughened intermediate/high temperature cured carbon fiber composites were prepared.The crystallinity of the particles,and their effect on the mechanical properties and microstructure of the composites.The presence of carbon nanotubes increases the crystallinity of the micro-nano particles,changes the structure of the particles after melt crystallization,and forms a multi-scale interface with the carbon fiber,which is beneficial to improve the fracture toughness of the composite material,and establishes the micro-nano particle structure change and interlayer toughening mechanism model.